| CPC G03G 15/0812 (2013.01) [G03G 15/0818 (2013.01); G03G 15/09 (2013.01)] | 11 Claims |

|
1. A developing apparatus for developing a latent image formed on an image bearing member comprising:
a developer carrying member configured to carry a developer including toner and magnetic carrier, said developer carrying member including a developer carrying surface having a plurality of grooves;
a magnet, provided inside said developer carrying member, configured to attract the developer on said developing carrying surface; and
a regulating member, provided spaced from said developer carrying member, configured to regulate an amount of the developer carried on said developer carrying surface,
wherein an amount M/S (mg/mm2) of the developer carried on a unit area of said developer carrying surface after passing by said regulating member, a gap SB (mm) between a free end of said regulating member and said developer carrying member, a depth D (mm) of said grooves, a density G (mg/mm3) of the developer, and a groove ratio α which is a ratio of said grooves in said developer carrying surface satisfy,
0.1≤M/S (mg/mm2)≤0.5,
0.2≤SB (mm),
¼×M/S (mg/mm2)≤α×{SB(mm)+D(mm)}×G(mg/mm3)<M/S (mg/mm2),
0.06≤α
wherein said magnet includes a pole at a position opposing said regulating member, and
wherein the pole is in a range of 40 mT to 70 mT in magnetic flux density.
|